Firefighters were called to two separate incidents, one in Canberra's northern suburbs and another in the far south of the ACT, late on Tuesday morning.
Emergency services were called to a house in Crofts Crescent, Spence, around 10.42am where they found a house well consumed by fire.
Ambulance and police also attended and the street was sealed off. Firefighters extinguished the blaze but are yet to enter the building or determine the cause.
At Tharwa near Lanyon Homestead, a burn-off by a private landholder got out of control around 11.20am which prompted the support of five ACT Rural Fire Service crews.
The grass fire has been brought under control. However, Tharwa Drive was closed to through traffic for a time and ESA has warned of an ongoing smoke hazard in the area.